Is Anaerobic Bacteria cultivation a common reality?

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I can cultivate aerobic bacteria on the surface of the media at almost any flow rate. I am trying to cultivate anaerobic bacteria, which is a strain of bacteria that will convert Nitrates to a harmless gas. Anerobic to Nitrates, Anaerobic to harmless Nitrogen gas. But, Anaerobic bacteria can not survive in an environment with oxygen present. According to Seachem, the flow rate has to be under 50 GPH when using "De*Nitrate" Matrix Media so that oxygen isn't introduced to the environment where you're trying to cultivate anaerobic bacteria in order to convert Nitrates to Nitrogen gas.

But seachem must surely understand that 50gph flow rate in any monster aquarium is basically a trickle! So lets say there advice works and you grow your lovely colony of nitrate neutralising anaerobic bacteria in a lab tank say at their recommended low flow rate, what happens when you practise your new findings on your monster show tank and start to flow your nitrate AND OXYGEN rich aquarium water through your colonised media at your aquariums turnover of umptyzillion gph! Total wipeout. But on a positive note, if seachem are right then there theory could work maybe on very small aquariums with very low gph turnover.
 
Yes, I've been reading up on what serves to feed the Anaerobic Bacteria, and that's where the science looses me. I'm dealing with a fresh water tank, and not sure what is needed to nourish anaerobic bacteria if anything beyond Nitrites.

I know that a marine tank is a different matter, and I know there are significant potential complications with respect to bi-products that are likely to be produced from nourishing the anaerobic bacteria, various gases, etc...

But with respect to the average hobbyist having success in actually cultivating anaerobic bacteria that flourish to the point of consistently converting Nitrates, it seems like success might be pretty illusive due to the complexities of doing so. I think that's why I seem to read so many testimonials in the various forums that almost nobody seems to achieve the actual goal, which is conversion of Nitrates to gas.

I am considering a fluidized sand filter...I know some are using sulfer based DeNitrators, and that some have tried Media based DeNitrators, etc...but, the most successes I've read about, with the least amount of fiddling with adjustments, and/or catastrophic failures that introduce toxins back into the tank, kill fish, etc... is the fluidized sand filter.

Converting Nitrate to Nitrogen is a bit more complex than that. You need to supply the right 'food' for the right metabolic pathway.

Some reef keepers use Ethanol/Methanol, but you can make CO2 via fermentation. The advantage of feeding the CO2 into the set up this way, the gas isnt dried or cleaned so contains very small amounts of alcohol into the system, this help the bacteria to utilize the Nitrate via a different pathway and produce Nitrogen.

i have tried to be really basic here with this, but if you want detailed info let me know.
 
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Yeah, a Monster tank would require a LOT of media to be effective...So, probably not practical through the use of a HOB filter. That's where I think the fluidized sand filters, or even the sulfur based type, or even media based automated Denitrators specified based on tank size would be the better alternative to trying to do what I'm trying to accomplish using a HOB filter in a small 30 gallon tank. The automatic Denitrators do require a certain flow control to be effective, and that can be introduced via a canister filter or power head using a flow control valve to regulate flow. But, at least the reactors would be properly sized for the tank with respect to whatever media is being used.

But seachem must surely understand that 50gph flow rate in any monster aquarium is basically a trickle! So lets say there advice works and you grow your lovely colony of nitrate neutralising anaerobic bacteria in a lab tank say at their recommended low flow rate, what happens when you practise your new findings on your monster show tank and start to flow your nitrate AND OXYGEN rich aquarium water through your colonised media at your aquariums turnover of umptyzillion gph! Total wipeout. But on a positive note, if seachem are right then there theory could work maybe on very small aquariums with very low gph turnover.
 
Well, the 9 GPH flow rate would be more akin to a swamp than the 28 GPH flow rate...

I want to say that goes back to the flow in the filter, essentially creating a stagnant area for the bacteria to grow, think of it like a swamp on the edge of a pond. Theres little to no flow there, and by contrast probably not much O2.
 
Nitrates supply the nitrogen, but the bacteria need a source of carbon for the correct metabolic pathway to function. the easiest way is to use methanol or Ethanol as a feed source.

The easiest for the home hobbyist is to use CO2 from a basic sugar/water/ yeast mix, you get very tiny amounts of secondary alcohols produced that get into the filter, this provides the carbon feed source.

There are other anerobic pathways, sulphur is another common one, but this makes......Sulphur Dioxide.
 
I have alot on at the moment, but i will dig you out some information, nitrogen gas via a filter is the hard way to deal with Nitrate. Plants are much quicker and easier, they dont have to be int the aquarium. Aquaponics work well for this.
 
I suppose dealing with Nitrates is more complicated than most think, which may be why so many have commented in the forums that they've tried the Anaerobic route but failed.

I've had plants in my aquariums in the past, but they often present their own set of challenges with respect to lighting and nourishment. Plants have their own challenges, so I've been experimenting with bio-media in hopes I could make the full nitrogen cycle work for me. It seems that many have become frustrated in trying to use bio media, and that very few have actually mastered it. So, maybe I'm engaged in a fools errand with respect to bio media...

I'll be interested in knowing about Aquaponics when you get time, and thanks!

I have alot on at the moment, but i will dig you out some information, nitrogen gas via a filter is the hard way to deal with Nitrate. Plants are much quicker and easier, they dont have to be int the aquarium. Aquaponics work well for this.
 
I suppose dealing with Nitrates is more complicated than most think, which may be why so many have commented in the forums that they've tried the Anaerobic route but failed.

I've had plants in my aquariums in the past, but they often present their own set of challenges with respect to lighting and nourishment. Plants have their own challenges, so I've been experimenting with bio-media in hopes I could make the full nitrogen cycle work for me. It seems that many have become frustrated in trying to use bio media, and that very few have actually mastered it. So, maybe I'm engaged in a fools errand with respect to bio media...

I'll be interested in knowing about Aquaponics when you get time, and thanks!
For nitrate removal terrestrial plants are the way to go.

I would give greater detail but being the season etc etc.. I will do you a short version and remind me early in the new year, i will come back with alot of detail for you.

Depends how much Ammonia we are talking about at the start, if Ammonia isnt a problem then you can skip over the nitrite question, the role of Anaerobic media and Nitrite collide, so in short if your Ammonia isnt a problem we can go straight to dealing with nitrate and not nitrite.

The most effective method, would depend on roughly how much nitrate you generate in a day. If it was significant then you would go the mist and air injected CO2 into the root ball of a say a tomato plant (could be lettuce dosnt matter for now).

The set up is simple imagine a square section of PVC guttering, this has a fitting to take a pump hose one end and overflow pipe the other. The overflow goes into the tank.

If you produce so much nitrate you need to get rid of alot, then you use a suitable size vivarium mister, the kind that use ultrasonics to create an almost dry water mist, this is blown by a pc type fan into the guttering, the guttering has a lid on top. You can buy these at hydroponic shops.

You blow the ultra fine mist into one end of the pipe, directly underneath you inject very small amounts of CO2, the mist absorbs this as carbonic acid. This simply makes the carbon available easily for the roots.

Now depending on the size of tank, and the amount of Nitrate we are talking about, the details vary but the set up is roughly the same. If the nitrates are not massive then do away with misting and go two chamber guttering and 1/5th flow from filter into the guttering from a tee section.

Without pics its hard to get the setup in your head. So in the new year i will take you through it if you like. That method will outstrip any other type of setup, being terrestrial plant it is also self governing, the plants takes all the nitrate, you grow it SOG method.

So not enough nutrient and the plant dies back a bit, but the roots are fine, its the roots we worry about ;). In most situations lettuce plants will do as well but need changing every 8 weeks, toms last 18 months if done right.

Average daylight will do, or if you really have a huge sump filter and produce grams of nitrate a day, then you may need to add light, but rarely. There is alot more to it like buffering just after nitrate removal (easy to automate with a separate section and marble chips).

Messing with Anaerobic chambers is fun, but only needed in pretty special circumstances.
 
I get the impression from your description that the plant(s) are housed in some kind of separate tank with proper lighting, but apart from the aquarium, and linked through some tubes that supply the separate tank with the plant(s) with tank water that nourishes the plant(s), and a tube that also replenishes denitrated cleansed water to the aquarium. After the holidays are over, I look forward to learning more.

For nitrate removal terrestrial plants are the way to go.

I would give greater detail but being the season etc etc.. I will do you a short version and remind me early in the new year, i will come back with alot of detail for you.

Depends how much Ammonia we are talking about at the start, if Ammonia isnt a problem then you can skip over the nitrite question, the role of Anaerobic media and Nitrite collide, so in short if your Ammonia isnt a problem we can go straight to dealing with nitrate and not nitrite.

The most effective method, would depend on roughly how much nitrate you generate in a day. If it was significant then you would go the mist and air injected CO2 into the root ball of a say a tomato plant (could be lettuce dosnt matter for now).

The set up is simple imagine a square section of PVC guttering, this has a fitting to take a pump hose one end and overflow pipe the other. The overflow goes into the tank.

If you produce so much nitrate you need to get rid of alot, then you use a suitable size vivarium mister, the kind that use ultrasonics to create an almost dry water mist, this is blown by a pc type fan into the guttering, the guttering has a lid on top. You can buy these at hydroponic shops.

You blow the ultra fine mist into one end of the pipe, directly underneath you inject very small amounts of CO2, the mist absorbs this as carbonic acid. This simply makes the carbon available easily for the roots.

Now depending on the size of tank, and the amount of Nitrate we are talking about, the details vary but the set up is roughly the same. If the nitrates are not massive then do away with misting and go two chamber guttering and 1/5th flow from filter into the guttering from a tee section.

Without pics its hard to get the setup in your head. So in the new year i will take you through it if you like. That method will outstrip any other type of setup, being terrestrial plant it is also self governing, the plants takes all the nitrate, you grow it SOG method.

So not enough nutrient and the plant dies back a bit, but the roots are fine, its the roots we worry about ;). In most situations lettuce plants will do as well but need changing every 8 weeks, toms last 18 months if done right.

Average daylight will do, or if you really have a huge sump filter and produce grams of nitrate a day, then you may need to add light, but rarely. There is alot more to it like buffering just after nitrate removal (easy to automate with a separate section and marble chips).

Messing with Anaerobic chambers is fun, but only needed in pretty special circumstances.
 
Its a bit simpler than that, often natural light in the room is ok, the container dosnt matter so much. Its the principle of the system and how it works that you will need to focus on, the actual set up can be modified to your own situation and space etc.

When we go into it, you will need a rough idea how much nitrate we are talking about, this is a simply thing. You measure the nitrate before a water change, do the water change and then just before you do the next measure the nitrate again.

If you want more accurate figures, then lets say you do a water change weekly. Test the Nitrate etc before this change, do the water change and test the nitrate 30 mins after the change. This figure is your base figure, then test each day. The amount your nitrate goes up each day is the daily amount, sometimes it can be 2-3 days before the nitrate increases enough to measure. Thats fine, just keep testing upto the next change.

When we do it on larger systems we use titration every 12 hours for an accurate figure, you wont need this accuracy. When you build the nitrate filter you will add 40% capacity to it, depending on which principle you go with, you will have to add a mineral section.
This is because, once you get a AP system tuned in, it will strip all minerals etc out of the water, some you will want to put back.

This is normally done by adding marble chips or water to a separate section, this separate section is normally the last stage before the tank return.

As part of the course we are going to be running, i need to do an extensive write up on this kind of thing anyway. Its likely i will link you to a page for me to use elsewhere later, but the discussion we will keep here as the page will be moved at some point.

It saves me writing the same material twice.
 
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